Prior video signal interframe coding, transmission and reproduction systems initially encode a base frame image. This base frame image incorporates both the low and the high spatial frequency components of the image. The base frame image is transmitted and thereafter only information representative of the difference between the base frame and each subsequent image is transmitted. Both low and high frequency spatial components are contained within the difference information. Using the base frame image and the subsequent difference information a high quality version, i.e., an accurate or error free representation, of any desired subsequent image can be reconstructed. If difference information is lost during transmission, only a low quality version of the desired image, i.e. an inaccurate or error strewn representation, can be reconstructed. Such prior arrangements are inefficient because they lack the ability to rapidly reproduce high quality images in random access applications. Similarly, this prior arrangement requires a long time to recover from loss of the difference information caused by transmission errors. The inefficiency and delays are caused by the leveraged encoding of each image beyond the base frame since all of the information prior to the selected frame is required, i.e., all the information contained in the base frame and all the difference information relating to each sequentially subsequent image. However, it is known that interframe coding tends to reduce the number of bits that are required to be transmitted.
In a prior attempt to reduce the reconstruction difficulty a new base frame is periodically incorporated into the bit stream. However, this technique dramatically increases the average number of bits required to represent all the information in an average frame because each base frame is encoded using intraframe coding and all of the information representing a base frame is used by each subsequent image. It is known that intraframe coding tens to require a larger number of bits than intraframe coding. In intraframe coding, characteristics of neighboring picture elements (pels or pixels are predicted based on the values of those characteristics of neighboring pels in the same frame, and the error or difference between the actual value and the predicted value is encoded. This type of encoding is illustrated in an article entitled "Adaptive Coding of Monochrome and Color Images", IEEE Trans. Communication, Vol. COM-25, pp. 1285-1292, Nov. 1977.